How about this?
I think you're a pilot from the moment you start to plan a flight, and continue to be a pilot, until the moment you put the airplane safely into the hangar, and completed the paper work.
But you're also an aviator, from the moment the main wheels defy gravity and leave the ground behind, until your wheels and the ground make up, and gently kiss again.
To me being a pilot is about professionalism, and being an aviator is about the passion of flight. Though I'm sure my dictionary would disagree
dp